Diagnostic Imaging and Testing in Neurological Assessment

Diagnostic tests and procedures are vital tools that help physicians confirm or rule out the presence of a neurological disorder or other medical condition. Advances in medicine, technology, and pharmacology have contributed to safer outcomes for children who may need sedation for diagnostic tests. Imaging or other tests may be performed to obtain a baseline for future studies.

In general, radiographic or digital imaging is looking at brain structure, while other diagnostic tests like electroencephalogram (EEG), single photon emission computed tomography scanning (SPECT), nuclear medicine scans, and Wada tests are evaluating specific functions of the brain. Positron emission tomography (PET) scans look at metabolic function and utilization of glucose by the brain. Newer technologies allow for the evaluation of cerebral blood flow and brain perfusion. Some tests serve both diagnostic and therapeutic outcomes.

Neurological examinations
Neurological examination assess your motor and sensory skills, the functioning of cranial nerves, hearing and speech, vision, coordination and balance, mental status, and changes in mood or behavior, among other abilities. Diagnostic tools including a tuning fork, flashlight, reflex hammer, ophthalmoscope, and needles are used to help diagnose:

• brain tumors
• infections such as encephalitis and meningitis
• Parkinson’s disease
• Huntington’s disease
• Amyotrophic Lateral Sclerosis (ALS)
• epilepsy.

Some tests require the services of a specialist to perform and analyze results.

Electroencephalography (EEG)

Electroencephalography, or EEG, monitors brain activity through the skull.  EEG is used to help diagnose certain seizure disorders, brain tumors, brain damage from head injuries, inflammation of the brain and/or spinal cord, alcoholism, certain psychiatric disorders, and metabolic and degenerative disorders that affect the brain. EEGs are also used to evaluate sleep disorders, monitor brain activity when a patient has been fully anesthetized or loses consciousness, and confirm brain death.

This painless, risk-free test can be performed in a doctor’s office or at a hospital or testing facility. Prior to taking an EEG, the person must avoid caffeine intake and prescription drugs that affect the nervous system. A series of cup-like electrodes are attached to the patient’s scalp.  These electrodes (also called leads) are small devices that are attached to wires and carry the electrical energy of the brain to a machine for reading.

 

PET Scanning (Positron Emission Tomography)
Disease is a biological process, beginning long before we are aware of it. Mobile Positron Emission Tomography (PET), allows doctors to view the organ systems of our body and how they are functioning. Physicians can see how the body's cells are functioning and the exact location of a disease.

PET is an imaging procedure that gives information not available through CT, MRI, x-ray, blood test or physical examination. PET is an invaluable clinical test for cancer, heart disease and neurological disorders, and is used more and more to diagnose patients with these serious afflictions.

• In neurology, PET is able to detect early signs of Alzheimer's, Parkinson's and Huntington's diseases, epilepsy and other disorders, even before some symptoms occur, making a critical difference in their treatment and management. PET detects the onset of Alzheimer's disease two to three years before any other diagnosis can be made, and in the case of hereditary Alzheimer's, PET can detect the disease before symptoms occur.
  
  
• PET is a safe and painless procedure, which typically takes about one or two hours to complete. Patients are injected with a small amount of non-dangerous radioactive sugar, and then rest for about an hour to wait for the body to process the sugar. In the mobile PET scanning room, the patient lies on a table that slowly passes through the scanner.